Preoperative diagnostic value of coronary CT angiography in acute Stanford type A aortic dissection involving the coronary arteries

AIM

To assess the diagnostic value of coronary computed tomography angiography (CCTA) in acute type A aortic dissection (ATAAD) with coronary artery involvement and to evaluate whether CCTA could provide potentially useful information for selecting the surgical method.

MATERIALS AND METHODS

Patients with ATAAD treated from January 2019 to December 2020 were reviewed retrospectively. Involvement of the coronary arteries based on CCTA findings were grouped into three major types and five subtypes. Interobserver and intraobserver diagnostic agreement for five subtypes were determined. The patients were divided into the coronary artery bypass grafting (CABG) and non-CABG groups, and the proportions of the five subtypes between the two groups were compared.

RESULTS

A total of 95 patients were enrolled in this study. Interobserver and intraobserver diagnostic agreement were both substantial in the left and right coronary arteries. Overall, the proportions of the five subtypes of coronary artery involvement were significantly different between the two groups (p<0.001). The proportion of Type A was elevated in the non-CABG group compared with the CABG group (22.6% versus 71.9%); by contrast, the proportions of Type B1 (35.5% versus 14.1%), Type B2 (19.4% versus 10.9%), Type C1 (6.5% versus 0%), and Type C2 (16.1% versus 3.1%) were elevated in the CABG group.

CONCLUSION

CCTA is reliable in evaluating coronary artery involvement by ATAAD. The present retrospective study indicated that CABG may be considered if the intimal flap disrupts the coronary orifice and causes luminal stenosis >50%, particularly Type B, or if an intimal tear occurs in the coronary orifice (Type C), which deserve further validation through prospective studies.

Lessons on fruiting body morphogenesis from genomes and transcriptomes of Agaricomycetes

Fruiting bodies (sporocarps, sporophores or basidiomata) of mushroom-forming fungi (Agaricomycetes) are among the most complex structures produced by fungi. Unlike vegetative hyphae, fruiting bodies grow determinately and follow a genetically encoded developmental program that orchestrates their growth, tissue differentiation and sexual sporulation. In spite of more than a century of research, our understanding of the molecular details of fruiting body morphogenesis is still limited and a general synthesis on the genetics of this complex process is lacking. In this paper, we aim at a comprehensive identification of conserved genes related to fruiting body morphogenesis and distil novel functional hypotheses for functionally poorly characterised ones. As a result of this analysis, we report 921 conserved developmentally expressed gene families, only a few dozens of which have previously been reported to be involved in fruiting body development. Based on literature data, conserved expression patterns and functional annotations, we provide hypotheses on the potential role of these gene families in fruiting body development, yielding the most complete description of molecular processes in fruiting body morphogenesis to date. We discuss genes related to the initiation of fruiting, differentiation, growth, cell surface and cell wall, defence, transcriptional regulation as well as signal transduction. Based on these data we derive a general model of fruiting body development, which includes an early, proliferative phase that is mostly concerned with laying out the mushroom body plan (via cell division and differentiation), and a second phase of growth via cell expansion as well as meiotic events and sporulation. Altogether, our discussions cover 1 480 genes of Coprinopsis cinerea, and their orthologs in Agaricus bisporus, Cyclocybe aegerita, Armillaria ostoyae, Auriculariopsis ampla, Laccaria bicolor, Lentinula edodes, Lentinus tigrinus, Mycena kentingensis, Phanerochaete chrysosporium, Pleurotus ostreatus, and Schizophyllum commune, providing functional hypotheses for ~10 % of genes in the genomes of these species. Although experimental evidence for the role of these genes will need to be established in the future, our data provide a roadmap for guiding functional analyses of fruiting related genes in the Agaricomycetes. We anticipate that the gene compendium presented here, combined with developments in functional genomics approaches will contribute to uncovering the genetic bases of one of the most spectacular multicellular developmental processes in fungi. Citation: Nagy LG, Vonk PJ, Künzler M, Földi C, Virágh M, Ohm RA, Hennicke F, Bálint B, Csernetics Á, Hegedüs B, Hou Z, Liu XB, Nan S, M. Pareek M, Sahu N, Szathmári B, Varga T, Wu W, Yang X, Merényi Z (2023). Lessons on fruiting body morphogenesis from genomes and transcriptomes of Agaricomycetes. Studies in Mycology 104: 1-85. doi: 10.3114/sim.2022.104.01.

Response of nitrite accumulation to elevated C/NO- 3-N ratio during partial denitrification process: Insights of extracellular polymeric substance, microbial community and metabolic function

This study investigated the response of nitrite accumulation to elevated COD/NO₃^--N ratio (C/N) during partial denitrification (PD). Results indicated nitrite was gradually accumulated and remained stable (C/N = 1.5 ∼ 3.0), while that rapidly declined after reaching the peak (C/N = 4.0 ∼ 5.0). The polysaccharide (PS) and protein (PN) content of tightly-bound extracellular polymeric substances (TB-EPS) reached the maximum at C/N of 2.5 ∼ 3.0, which might be stimulated by high level of nitrite. Illumina MiSeq sequencing showed Thauera and OLB8 were dominated denitrifying genera at C/N of 1.5 ∼ 3.0, while Thauera was further enriched with fading OLB8 at C/N of 4.0 ∼ 5.0. Meanwhile, the highly-enriched Thauera might enhance the activity of nitrite reductase (nirK) promoting further nitrite reduction. Redundancy analysis (RDA) showed positive correlations between nitrite production and PN content of TB-EPS, denitrifying bacteria (Thauera and OLB8) and nitrate reductases (narG/H/I) in low C/N. Finally, their synergistic effects for driving nitrite accumulation were comprehensively elucidated.

Advanced nitrogen removal from low carbon nitrogen ratio domestic sewage via continuous plug-flow anaerobic/oxic/anoxic system: Enhanced by endogenous denitrification

An anaerobic/oxic/anoxic continuous plug-flow biorereactor was established to derive stable advanced nitrogen removal of oligotrophic domestic wastewater by setting a sludge dual-reflux system and a mixed liquid cross-flow system, while extending the hydraulic retention time in anoxic section. The effluent total inorganic nitrogen was 7.9 ± 2.2 mg N/L, with removal efficiency of 84 ± 3.9%. Results of nitrogen balance calculations indicated that the contribution of simultaneous nitrification and denitrification to total inorganic nitrogen loss in oxic region was 15% during stable stage, and the total inorganic nitrogen removal by endogenous-denitrification and enhanced exogenous-denitrification in the anoxic region was 39.9%. Prolongation of hydraulic retention time in anoxic segment is the critical reason for enhancing endogenous-denitrification, and cross-flow system is an important measure to improve exogenous-denitrification. This study provides new insights into bridging the gap between energy-saving and high-level nitrogen removal from municipal wastewater with low carbon to nitrogen ratios.

Learning the protein language of proteome-wide protein-protein binding sites via explainable ensemble deep learning

Protein-protein interactions (PPIs) govern cellular pathways and processes, by significantly influencing the functional expression of proteins. Therefore, accurate identification of protein-protein interaction binding sites has become a key step in the functional analysis of proteins. However, since most computational methods are designed based on biological features, there are no available protein language models to directly encode amino acid sequences into distributed vector representations to model their characteristics for protein-protein binding events. Moreover, the number of experimentally detected protein interaction sites is much smaller than that of protein-protein interactions or protein sites in protein complexes, resulting in unbalanced data sets that leave room for improvement in their performance. To address these problems, we develop an ensemble deep learning model (EDLM)-based protein-protein interaction (PPI) site identification method (EDLMPPI). Evaluation results show that EDLMPPI outperforms state-of-the-art techniques including several PPI site prediction models on three widely-used benchmark datasets including Dset_448, Dset_72, and Dset_164, which demonstrated that EDLMPPI is superior to those PPI site prediction models by nearly 10% in terms of average precision. In addition, the biological and interpretable analyses provide new insights into protein binding site identification and characterization mechanisms from different perspectives. The EDLMPPI webserver is available at http://www.edlmppi.top:5002/ .

Advanced aromatic organic compounds removal from refractory coking wastewater in a step-feed three-stage integrated A/O bio-filter: Spectrum characterization and biodegradation mechanism

Extensive presence of aromatic organic compounds (AOCs) is a major course for the non-biodegradability of coking wastewater (COW). In-depth understanding of bio-degradation of AOCs is crucial for optimizing the design and operation of COW biological treatment systems in practical applications. Herein, the behavior and fate of AOCs were explored in a lab-scale step-feed three-stage integrated A/O biofilter (SFTIAOB) treating synthetic COW. Long-term operation demonstrated that COD, phenol, indole, quinoline and pyridine could be simultaneously removed. Phenol and indole were chiefly removed by anoxic zones, while quinoline and pyridine removal occurred in both anoxic and aerobic zones. Ultraviolet-visible spectrum observed that initial carboxylation and subsequent ring cracking and mineralization. Infrared spectroscopy also confirmed that key functional groups were cracked and produced during AOCs bio-degradation. Three-dimensional fluorescence spectrum indicated that significant transformation and elimination of tryptophan and humic acid with high molecular weight. Ring cleavage, distinct degradation and even complete mineralization of complex AOCs were further verified by gas chromatography-mass spectrometry. Moreover, functional degrading bacteria and aromatic ring-cleavage enzymes was successfully identified. Finally, AOCs biodegradation mechanisms by alternating anoxic and aerobic treatment was unraveled. This research provides thorough insights on AOCs biodegradation using a step-feed multi-stage alternating anoxic/oxic COW treatment process.

HCRNet: high-throughput circRNA-binding event identification from CLIP-seq data using deep temporal convolutional network

Identifying genome-wide binding events between circular RNAs (circRNAs) and RNA-binding proteins (RBPs) can greatly facilitate our understanding of functional mechanisms within circRNAs. Thanks to the development of cross-linked immunoprecipitation sequencing technology, large amounts of genome-wide circRNA binding event data have accumulated, providing opportunities for designing high-performance computational models to discriminate RBP interaction sites and thus to interpret the biological significance of circRNAs. Unfortunately, there are still no computational models sufficiently flexible to accommodate circRNAs from different data scales and with various degrees of feature representation. Here, we present HCRNet, a novel end-to-end framework for identification of circRNA-RBP binding events. To capture the hierarchical relationships, the multi-source biological information is fused to represent circRNAs, including various natural language sequence features. Furthermore, a deep temporal convolutional network incorporating global expectation pooling was developed to exploit the latent nucleotide dependencies in an exhaustive manner. We benchmarked HCRNet on 37 circRNA datasets and 31 linear RNA datasets to demonstrate the effectiveness of our proposed method. To evaluate further the model's robustness, we performed HCRNet on a full-length dataset containing 740 circRNAs. Results indicate that HCRNet generally outperforms existing methods. In addition, motif analyses were conducted to exhibit the interpretability of HCRNet on circRNAs. All supporting source code and data can be downloaded from https://github.com/yangyn533/HCRNet and https://doi.org/10.6084/m9.figshare.16943722.v1. And the web server of HCRNet is publicly accessible at http://39.104.118.143:5001/.

Insight into correlation of advanced nitrogen removal with extracellular polymeric substances characterization in a step-feed three-stage integrated anoxic/oxic biofilter system

As a core component of the biomass, the important role of extracellular polymeric substances (EPS) on treatment performance has been recognized. However, the comprehensive understanding of its correlation with nitrogen removal remains limited in biofilm-based reactors. In this study, the relevance between EPS and advanced nitrogen removal in a novel step-feed three-stage integrated anoxic/oxic biofilter (SFTIAOB) was specifically investigated. The operation showed as high as 81% TN removal was achieved under optimal conditions. Among the whole reactor, 2nd anoxic (A2) zone was the largest contributor for nitrogen removal, followed by the 3rd anoxic (A3) and 2nd oxic (O2) zones. EPS composition analysis found that high content of polysaccharides in tightly bound-EPS (A2 and A3) and protein in loosely bound-EPS and tightly bound-EPS (O2). Fourier transform infrared spectroscopy, three-dimensional fluorescence spectrum further verified stratified EPS subfractions containing different secondary protein structures, while 3-turn helix and tryptophan-like protein was the main reason for nitrogen removal. High-throughput sequencing revealed the co-existence of nitrogen removal-associated genera accomplished nitrification/denitrification combined with aerobic denitrification and anammox. Moreover, the correlation of EPS and microbial composition with nitrogen removal was clarified by redundancy analysis (RDA). Finally, potential mechanism for nitrogen removal was illuminated. This research gives more insight into EPS characteristics in enhancing nitrogen removal during the operation and optimization of a step-feed multi-stage A/O biofilm process.

Symptomatic and Asymptomatic Chronic Carotid Artery Occlusion on High-Resolution MR Vessel Wall Imaging

BACKGROUND AND PURPOSE

Chronic carotid artery occlusion remains a poorly understood risk factor for subsequent stroke, and potential revascularization is dependent on understanding the anatomy and nature of the occlusion. Luminal imaging cannot assess the nature of an occlusion, so the internal structure of the occlusion must be inferred. The present study examines the signal characteristics of symptomatic and asymptomatic carotid occlusion that may point to management differentiation.

MATERIALS AND METHODS

We prospectively recruited patients who were diagnosed with chronic carotid artery occlusion defined as longer than 4 weeks and confirmed by DSA. All patients underwent high-resolution MR vessel wall imaging examinations after enrollment. Baseline characteristics, vessel wall imaging features, and DSA features were collected and evaluated. The vessel wall imaging features included segment involvement, signal intensity, contrast enhancement, and vessel wall thickness. The symptomatic and asymptomatic chronic carotid artery occlusions were compared.

RESULTS

A total of 44 patients with 48 lesions were included in this study from February 2020 to December 2020. Of the 48 lesions, 35 (72.9%) were symptomatic and 13 (27.1%) were asymptomatic. There was no difference in baseline and DSA features. On vessel wall imaging, C1 and C2 were the most commonly involved segments (91.7% and 68.8%, respectively). Compared with symptomatic lesions, asymptomatic lesions were more often isointense (69.2%) in the distal segment (P = .03). Both groups had diffuse wall thickening (80% and 100%).

CONCLUSIONS

Signal characteristics between those with symptomatic and asymptomatic carotid artery occlusions differ in a statistically significant fashion, indicating a different structure of the occlusion.

Cross-genera amplification and identification of Colpodella sp. with Cryptosporidium primers in fecal samples of zoo felids from northeast China

The protozoans include many intracellular human pathogens. Accurate detection of these pathogens is necessary to treat the diseases. In clinical epidemiology, molecular identification of protozoan is considered a more reliable and rapid method for identification than microscopy. Among these protozoans, Cryptosporidium considered being one of the important water-borne zoonotic pathogens and a major cause of a diarrheal disease named cryptosporidiosis in humans, domestic animals, and wild animals. This study was aimed to identify Cryptosporidium in zoo felids (N= 56) belonging to different zoo of China, but accidentlly Colpodella was encountered in the zoo felids sample and phylogenetic data confirmed this unexpected amplification from fecal samples using two-step nested-PCR. Phylogenetic analysis revealed the fact about the specific primers used previously by many researchers and cross-genera amplification. We came to know that genetically sequenced amplicon gives more accurate identification of species. This study suggests more investigation on Colpodella which has been neglected previously but gains the attention of researchers after identified from humans and animals and has been known to correlate with neurological symptoms in patients.

Impact of age and menopausal stage on serum anti-Müllerian hormone levels in middle-aged women

OBJECTIVE

This study aimed to evaluate the association between age, menopausal stage and serum anti-Müllerian hormone (AMH) levels in middle-aged women.

METHODS

In this cross-sectional study, the serum AMH levels of 288 healthy women aged 40-55 years (divided into age groups: 40-44, 45-49 and 50-55 years) were evaluated. Stages of Reproductive Aging Workshop + 10 criteria were used to categorize these women into menopausal stages: late reproductive, menopausal transition and early postmenopausal stages. The impact of age, menopausal stage and hormone replacement therapy on serum AMH levels was analyzed using multi-factor analysis of variance. Effects of body mass index, smoking status and oral contraceptive use were simultaneously considered.

RESULTS

The median AMH level was 0.140 ng/ml. Log-AMH levels varied according to age group (variance = 20.113, F = 88.538, p < 0.001) and menopausal stage (variance = 5.543, F = 24.501, p < 0.001). An exponential model defined as AMH = 227,421.757 × e^{(-0.301 × age)} was fit to describe the decline in AMH level with age. The 5th-95th percentiles of the AMH levels ranged from less than 0.020 to 3.150, less than 0.020 to 1.944 and less than 0.020 to 0.030 ng/ml in the aforementioned menopausal stages, respectively.

CONCLUSION

Age and menopausal stage were associated with AMH levels; age had a greater impact on AMH than menopausal stage in middle-aged women.

iDeepSubMito: identification of protein submitochondrial localization with deep learning

Mitochondria are membrane-bound organelles containing over 1000 different proteins involved in mitochondrial function, gene expression and metabolic processes. Accurate localization of those proteins in the mitochondrial compartments is critical to their operation. A few computational methods have been developed for predicting submitochondrial localization from the protein sequences. Unfortunately, most of these computational methods focus on employing biological features or evolutionary information to extract sequence features, which greatly limits the performance of subsequent identification. Moreover, the efficiency of most computational models is still under explored, especially the deep learning feature, which is promising but requires improvement. To address these limitations, we propose a novel computational method called iDeepSubMito to predict the location of mitochondrial proteins to the submitochondrial compartments. First, we adopted a coding scheme using the ProteinELMo to model the probability distribution over the protein sequences and then represent the protein sequences as continuous vectors. Then, we proposed and implemented convolutional neural network architecture based on the bidirectional LSTM with self-attention mechanism, to effectively explore the contextual information and protein sequence semantic features. To demonstrate the effectiveness of our proposed iDeepSubMito, we performed cross-validation on two datasets containing 424 proteins and 570 proteins respectively, and consisting of four different mitochondrial compartments (matrix, inner membrane, outer membrane and intermembrane regions). Experimental results revealed that our method outperformed other computational methods. In addition, we tested iDeepSubMito on the M187, M983 and MitoCarta3.0 to further verify the efficiency of our method. Finally, the motif analysis and the interpretability analysis were conducted to reveal novel insights into subcellular biological functions of mitochondrial proteins. iDeepSubMito source code is available on GitHub at https://github.com/houzl3416/iDeepSubMito.

Traumatic fractures in China from 2012 to 2014: a National Survey of 512,187 individuals

The China National Fracture Study has been conducted to provide a national dataset of traumatic fractures across China. A national representative sample of 512,187 individuals was selected. The population-weighted incidence rates, distribution, injury mechanisms, and risk factors for traumatic fractures were identified for various groups of individuals.

INTRODUCTION

The China National Fracture Study (CNFS) has been conducted to provide a comprehensive and up-to-date national dataset of traumatic fractures across China. This study aims to report the national incidences and distributions of traumatic fractures that occurred in 2012, 2013, and 2014 and to analyze the risk factors.

METHODS

A national representative sample of individuals was selected from 24 rural counties and 24 urban cities of 8 provinces using stratified random sampling and the probability proportional to size (PPS) methodology. Participants were interviewed to identify whether they sustained traumatic fractures of the trunk and/or four extremities that had occurred in 2012, 2013, and 2014. The main risk factors associated with traumatic fractures were analyzed by multiple logistic regression models.

RESULTS

A total of 512,187 individuals, including 259,649 males and 252,538 females, participated in the CNFS. The population-weighted incidence rates of traumatic fractures in China were calculated to be 2.5 (95% CI, 2.2-2.8) per 1000 population in 2012, 2.8 (95% CI, 2.5-3.3) in 2013, and 3.2% (95% CI, 2.8-3.6) in 2014. The population-weighted incidence rates of fragility fractures among participants aged 65 years and older were calculated to be 27.4 (95% CI, 21.4-33.4) per 1000 population in 2012, 36.0 (95% CI, 28.6-43.5) in 2013, and 42.4 (95% CI, 34.9-49.9) in 2014. The most common cause of fracture was low-energy injuries, followed by traffic accidents. For all age groups, sleeping less than 7 h was a risk factor for traumatic fractures. Alcohol consumption and previous fracture history were identified as risk factors for adults aged 15 years and over. Cigarette smoking was found to be a risk factor for males aged 15-64 years old. For individuals aged 15-64 years old, underweight incurred a risk effect for males and overweight for females. Alcohol consumption, sleeping less than 7 h per day, living in the central and eastern regions, a body mass index less of than 18.5, and having a previous fracture history were identified as strong risk factors for fragility fractures.

CONCLUSION

The national incidence, distribution, and injury mechanisms for traumatic fractures were revealed in the CNFS. Risk factors were identified for various groups of individuals.

iCircRBP-DHN: identification of circRNA-RBP interaction sites using deep hierarchical network

Circular RNAs (circRNAs) are widely expressed in eukaryotes. The genome-wide interactions between circRNAs and RNA-binding proteins (RBPs) can be probed from cross-linking immunoprecipitation with sequencing data. Therefore, computational methods have been developed for identifying RBP binding sites on circRNAs. Unfortunately, those computational methods often suffer from the low discriminative power of feature representations, numerical instability and poor scalability. To address those limitations, we propose a novel computational method called iCircRBP-DHN using deep hierarchical network for discriminating circRNA-RBP binding sites. The network architecture can be regarded as a deep multi-scale residual network followed by bidirectional gated recurrent units (BiGRUs) with the self-attention mechanism, which can simultaneously extract local and global contextual information. Meanwhile, we propose novel encoding schemes by integrating CircRNA2Vec and the K-tuple nucleotide frequency pattern to represent different degrees of nucleotide dependencies. To validate the effectiveness of our proposed iCircRBP-DHN, we compared its performance with other computational methods on 37 circRNAs datasets and 31 linear RNAs datasets, respectively. The experimental results reveal that iCircRBP-DHN can achieve superior performance over those state-of-the-art algorithms. Moreover, we perform motif analysis on circRNAs bound by those different RBPs, demonstrating that our proposed CircRNA2Vec encoding scheme can be promising. The iCircRBP-DHN method is made available at https://github.com/houzl3416/iCircRBP-DHN.

CDC6 is up-regulated and a poor prognostic signature in glioblastoma multiforme

PURPOSE

Glioblastoma multiforme (GBM) represents the most common and the most malignant type of brain tumor. Cell division cycle 6 (CDC6), a gene associated with DNA replication initiation, has been proven to be associated with the prognosis of multiple tumors. In this study, we aim to explore the association between CDC6 expression and GBM carcinogenesis and prognosis.

METHODS

CDC6 expression in normal cells and GBM cells was explored by analyzing TCGA dataset, as well as by RT-PCR and western blot methods. Survival analysis was performed by the Kaplan-Meier method. Multivariate Cox-regression analysis was adopted to estimate the independence of CDC6 as a GBM prognostic factor.

RESULTS AND CONCLUSIONS

Elevated CDC6 levels in GBM tumor tissues compared with those in normal brain tissues were illustrated by analyzing the gene expression profiles from TCGA dataset, and confirmed by RT-PCR and western blot assays in GBM tumor and normal human astrocyte cell lines. Kaplan-Meier analysis indicated the negative influence of high CDC6 expression on GBM overall survival (OS) probability and days to progression (D2P) after initial treatment, but not on days to recurrence (D2R) after initial treatment. Multivariate Cox regression analysis showed CDC6 as an independent signature marker gene for GBM prognosis. In addition, the combination of CDC6 mRNA expression and CpG island methylator phenotype (CIMP) could sensitively predict 3-year OS and D2P. In conclusion, our study uncovered the role of CDC6 in GBM carcinogenesis and prognosis for the first time, which could shed new light on GBM diagnosis and treatment.

Electro-Fenton with peroxi-coagulation as a feasible pre-treatment for high-strength refractory coke plant wastewater: Parameters optimization, removal behavior and kinetics analysis

Electro-Fenton (EF) with peroxi-coagulation (PC) as an emerging electro-chemical advanced oxidation method has been extensively applied to treat refractory wastewater. However, the studies on the pretreatment of the raw coke plant wastewater by EF process were still lacking. In this study, a lab-scale EF system (Fe as anode and graphite as cathode) achieved the highest COD removal of 69.2% based on the preliminary experiments. The process parameters and corresponding COD removal performance were further optimized using response surface methodology (RSM) combined with Box-Behnken experimental design (BBD). The optimal conditions were obtained as: 3.2 mA cm^-2 of current density, 2 h of the reaction time and 2.6 of the initial pH value, with the COD removal reaching 70.0%. Fourier infrared (FTIR), fluorescence excitation-emmission matrix (EEM) and gas chromatography-mass spectrometry (GC-MS) also revealed the degradation behaviors of dissolved organic matters (DOMs) by characterizing their structures and compositions before and after EF pretreatment, thus greatly improving the biodegradability of the wastewater. Moreover, the EF process for COD removal well followed third-order kinetics model. These findings give helpful guidance to design, optimize and control the EF process as a favourable pretreatment for actual refractory coking wastewater in practice.

Expression of C1q/TNF-related protein-3 (CTRP3) in serum of patients with gestational diabetes mellitus and its relationship with insulin resistance

OBJECTIVE

In this study, the changes of insulin resistance (IR) and pancreatic β-cell function in GDM patients were observed, changes of CTRP3 level in fasting serum and relationships with plasma glucose (PG) and pancreatic β-cell function were explored at the same time, and the correlation between serum CTRP3 and body mass index (BMI) was preliminarily discussed, providing a new way to identify the pathogenesis of GDM.

PATIENTS AND METHODS

Data of women from 24 to 28 weeks of pregnancy were collected. 100 women were selected to form gestational diabetes mellitus (GDM) group and another 100 women were chosen to constitute normal glucose tolerance (NGT) group according to the results of oral glucose tolerance test (OGTT). They were divided into GDM overweight/obesity (GDM + OW) group, GDM non-overweight/obesity (GDM + NW) group, simple overweight (OW) group and normal body weight (NW) group, according to whether the progestational body mass index (BMI) was higher than 24 kg/m2 before pregnancy. General information of all subjects, for example, age, last menstrual period, parity, diet, weight and height, were collected, and blood samples were taken from all subjects for use in detections of total cholesterol (TC), triglyceride (TG), very low-density lipoprotein (VLDL), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) and serum C1q/tumor necrosis factor-related protein-3 (CTRP3).

RESULTS

The levels of FPG, 1 h PG, 2 h PG, fasting CP (FCP), fasting insulin (FINS), homeostasis model assessment of IR (HOMA-IR), TG and VLDL-C in the GDM group, were significantly higher than those in the NGT group. TC and LDL-C in the GDM group were greater than those in the NGT group. Compared with that in the NGT group, homeostasis model assessment of β (HOMA-β) index was lower in the GDM group. From the NGT group to the GDM group, FPG, 1 h PG, 2 h PG, FINS and FCP had rising tendencies, and the differences were of statistical significance. Pearson correlation analysis indicated that HOMA-IR was positively correlated with pre-pregnancy BMI, FPG, 2 h PG, FINS, 1 h INS, 2 h INS, FCP, 1 h CP and 2 h CP in the GDM group, HOMA-β was negatively related to FPG. In the NGT group, there was a positive correlation between HOMA-IR and pre-pregnancy BMI. The level of CTRP3 in fasting serum of the GDM group was distinctly lower than that of the NGT group. Pearson correlation analysis revealed that in the GDM group, fasting serum CTRP3 had positive correlations with HOMA-β and HDL-C, but negatively associated with pre-pregnancy BMI, FPG, 1 h PG, 2 h PG, FCP, HOMA-IR, TG and VLDL-C. In the NGT group, the fasting serum CTRP3 was negatively correlated with pre-pregnancy BMI. Multiple linear stepwise regression analysis showed FPG was an independent influencing factor for fasting serum CTRP3.

CONCLUSIONS

With the increase of FPG, the progression of GDM IR patients is increased, and pancreatic β-cell function progressively declines. The decrease of CTRP3 level in fasting serum in GDM patients plays a metabolic role in the pathogenesis of GDM.

Genetic variation and phylogenetic analysis of Porcine circovirus type 2 in China from 2016 to 2018

Infection with Porcine circovirus type 2 (PCV2), the essential cause of porcine circovirus (PCV) associated diseases, is a growing problem in swine industry around the world. High nucleotide alteration leads to the constant evolution of PCV2 and outbreak of disease caused by PCV2. In this study, 48 PCV2 strains were isolated in China between 2016 and 2018 and the genetic diversity of these PCV2 isolates was determined. Results showed that these PCV2 isolates were classified into genotypes PCV2a (4 of 48), PCV2b (13 of 48) and PCV2d (31 of 48). Among them, 54.5% isolated in 2016, 65.2% isolated in 2017 and 71.4% isolated in 2018 belonged to PCV2d. It indicated that the prevalence of PCV2d genotype increased. All strains shared 93.4%-100% nucleotide sequence identity for the whole genome. Results of the analysis using RDP 4.0 molecular recombination software showed there were no recombinant events among the 48 PCV2 isolates in this study. Further analysis indicated the presence of higher amino acid residues diversity in important epitopes (43D/G, 115D/G, 134N/T, 165P/T, 169G/R/S, and 210E/G/D) in the predominant genotype PCV2d. Animal tests showed the viral titer of the PCV2d strain LN-3 in sera was higher than that of PCV2b strain HeB-1 at 14 and 21 days post-challenge, however, the differences were not statistically significant. There were also no obvious differences between PCV2d strain LN-3 and PCV2b strain HeB-1 in the amount of PCV2 antigen in lymphoid tissues. On the account of the increasing prevalence of PCV2d genotype, it is necessary to find the cause of PCV2 genotype change, to evaluate the effect of existing commercial vaccines and to develop new vaccines based on PCV2d genotype, if necessary. Keywords: epitope; PCV2d; phylogeny; Porcine circovirus type 2; recombination; genetic diversity.

[Derepression of CXCR7 indicates resistance to enzalutamide in castration resistant prostate cancer]

Objective: To investigate the effect of the derepression of chemokine receptor-7 (CXCR7) in prostatic tissues from patients with Castration Resistant Prostate Cancer (CRPC) on the resistance to enzalutamide (Enza). Methods: During the period of January 2015 to December 2017 all CRPC cases who underwent radical radiotherapy or androgen deprivation therapy (ADT) were evaluated. After prostatic puncture biopsy, the tissues were treated for immunostaining with CXCR7. Cox proportional hazard modeling and Kaplan-Meier analysis were used to determine PSA Progression-Free Survival (PSAP-FS) and Clinical or Radiographic Progression-Free Survival (CRP-FS) in the cohort. At last, PSA response rates and progression outcomes in CXCR7 negative cases and CXCR7 positive cases were analyzed. Results: Total 39 CRPC patients were enrolled in this study. And 23 cases derepress CXCR7, 16 cases negatively express CXCR7. The median follow-up duration was 12 months (range: 6-18) in the cohort. Chi-square analysis confirmed that PSA response rates after Enza treatment were significantly associated with CXCR7 derepression (χ(2)=22.129, P=0.000 06). Compared with CXCR7 positive expression group, CXCR7 negative expression group displayed improved median PSAP-FS (4.4 mon vs 11.7 mon, P=0.040 8) and CRP-FS (5.2 mon vs 13.1 mon, P=0.036 2) after Enza treatment. Conclusion: Derepression of CXCR7 in CRPC patients may be associated with resistance to enzalutamide. This protein may be novel target for treatment of CRPC.

Role of proton-coupled folate transporter in pemetrexed resistance of mesothelioma: clinical evidence and new pharmacological tools

BACKGROUND

Thymidylate synthase (TS) has a predictive role in pemetrexed treatment of mesothelioma; however, additional chemoresistance mechanisms are poorly understood. Here, we explored the role of the reduced-folate carrier (RFC/SLC19A1) and proton-coupled folate transporter (PCFT/SLC46A1) in antifolate resistance in mesothelioma.

PATIENTS AND METHODS

PCFT, RFC and TS RNA and PCFT protein levels were determined by quantitative RT-PCR of frozen tissues and immunohistochemistry of tissue-microarrays, respectively, in two cohorts of pemetrexed-treated patients. Data were analyzed by t-test, Fisher's/log-rank test and Cox proportional models. The contribution of PCFT expression and PCFT-promoter methylation to pemetrexed activity were evaluated in mesothelioma cells and spheroids, through 5-aza-2'-deoxycytidine-mediated demethylation and siRNA-knockdown.

RESULTS

Pemetrexed-treated patients with low PCFT had significantly lower rates of disease control, and shorter overall survival (OS), in both the test (N = 73, 11.3 versus 20.1 months, P = 0.01) and validation (N = 51, 12.6 versus 30.3 months, P = 0.02) cohorts. Multivariate analysis confirmed PCFT-independent prognostic role. Low-PCFT protein levels were also associated with shorter OS. Patients with both low-PCFT and high-TS levels had the worst prognosis (OS, 5.5 months), whereas associations were neither found for RFC nor in pemetrexed-untreated patients. PCFT silencing reduced pemetrexed sensitivity, whereas 5-aza-2'-deoxycytidine overcame resistance.

CONCLUSIONS

These findings identify for the first time PCFT as a novel mesothelioma prognostic biomarker, prompting prospective trials for its validation. Moreover, preclinical data suggest that targeting PCFT-promoter methylation might eradicate pemetrexed-resistant cells characterized by low-PCFT expression.

[Long-term oncologic outcomes of localized high-risk prostate cancer undergoing brachytherapy combined with external-beam radiation therapy and maximal androgen blockade]

Objective: To investigate the oncologic outcome and PSA kinetics of localized high-risk prostate cancer (PCa) patients treated with combination strategy of radiation therapy (RT) and maximal androgen blockade (MAB). Methods: We retrospectively reviewed the clinical data of 320 localized PCa patients undergoing RT+ MAB from 2001 to 2015. And radiation treatment protocol consisted of permanent prostate brachytherapy (PPB) at 110 Gy and EBRT at 45 Gy/23 fractions. Results: The median follow-up time was 90 (range: 12-186) months. And 117 (36.6%) cases underwent MAB + external-beam radiotherapy (EBRT), and other 203 (63.4%) cases received MAB+ EBRT+ PPB. Multivariate Cox regression analyses showed that PSA kinetics were positive indicators of oncologic outcomes. Furthermore, PSA kinetics were aberrantly improved by supplemental PPB to MAB+ EBRT as following, PSA nadir (1.3±0.7)μg/L vs(0.11±0.06)μg/L, time of PSA decrease to nadir (7.5±1.8)months vs (3.2±2.1)months, PSA doubling time (15.6±4.2)months vs (22.6±6.1)months, PSA decreasing amplitude (84.6±6.2)%vs(95.8±3.4)%. Additionally, the median time of several important oncologic events in MAB+ EBRT+ PPB group were also prolonged than that in MAB+ EBRT group as following, overall survival (12.3 years vs 9.1 years, P<0.001), biochemical recurrence-free survival (9.8 years vs 6.5 years, P<0.001), skeletal-related event (10.4years vs 8.2 years, P<0.001), and cytotoxic chemotherapy (11.6 years vs 8.8 years, P=0.007). Conclusion: MAB+ EBRT+ PPB is extremely effective combination strategy for localized high-risk PCa patients, and PPB plays the important synergistic role in improving PSA kinetics, which are independent predictor for oncologic outcomes.

Eyelid and fornix reconstruction in abortive cryptophthalmos: a single-center experience over 12 years

PurposeAbortive cryptophthalmos is a rare congenital eyelid anomaly with poor prognosis for vision and cosmesis. The study aims to present its varied manifestations and surgical outcomes.Patients and methodsThe medical records of patients with abortive cryptophthalmos treated at the Oculoplastic Clinic of Beijing Tongren Hospital between January 2004 and May 2016 were reviewed. Early surgical intervention was performed when exposure keratopathy occurs. Upper eyelid and superior fornix were mainly reconstructed with sliding myocutaneous flap and scleral and amniotic grafts. Post-operative upper eyelid contour, recurrence of symblepharon, and ability to retain prosthesis were evaluated.ResultsThe study included 41 eyes of 28 patients. The median age at first presentation was 5 years (ranging from 1 month to 58 years). The majority (79%) with concurrent craniofacial abnormalities tended to be associated with more severe cryptophthalmos. Nine eyes of 9 patients had recurrence of symblepharon. Acceptable functional and cosmetic outcomes were achieved in 20 of the 24 patients receiving repair procedures during the follow-up period.ConclusionOne-stage reconstruction of eyelid and fornix with scleral and amniotic grafts is an effective strategy to correct abortive cryptophthalmos.

Pretreatment Predictors of Early Response Revealed by Quantitative Cerebral Blood Flow in Major Depressive Disorder

Objective

The potential pattern of regional cerebral blood flow (rCBF) in major depressive disorder (MDD) underlies different response to antidepressants medication remain unclear. This study aimed to investigate the differences of rCBF between patients with different treatment response.

Methods

Eighty MDD patients [(44 treatment-responsive depression (RD) and 36 non-responding depression (NRD)] and 42 healthy controls (HC) underwent pulsed arterial spin labeling (PASL) scans in magnetic resonance imaging and clinical estimates. The exact rCBF values of each groups were obtained via quantification evaluation.

Results

Compared to NRD, the RD patients showed decreased rCBF values in frontal sensorimotor network (i.e. left paracentral lobule, left medial frontal gyrus, right superior frontal gyrus and right middle frontal gyrus), and further receiver operating curve (ROC) analyses demonstrated that the altered rCBF in these four regions exhibited outstanding performance on distinguishing NRD from RD. The NRD also exhibited reduced rCBF in bilateral cerebellum posterior lobe and right middle occipital gyrus and elevated rCBF in right postcentral gyrus and right middle frontal gyrus as compared to HC.

Conclusions

The decreased rCBF in frontal sensorimotor network appeared to be distinct characteristics for NRD, and might be severed as promising neuroimaging markers to differentiate depressed patients with weak early response to antidepressant medication. These findings expand our understanding of neural substrate underlying the antidepressant efficacy.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Antisense locked nucleic acids targeting agrA inhibit quorum sensing and pathogenesis of community-associated methicillin-resistant Staphylococcus aureus

AIM

Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) is commonly associated with nonnosocomial skin and soft tissue infections due to its virulence, which is mainly controlled by the accessory gene regulator (agr) quorum sensing (QS) system. In this study (KFF)₃ K peptide-conjugated locked nucleic acids (PLNAs) targeting agrA mRNA were developed to inhibit agr activity and arrest the pathogenicity of CA-MRSA.

METHODS AND RESULTS

Two PLNAs were designed, and synthesized, after predicting the secondary structure of agrA mRNA. The influence on bacterial growth was tested using a growth curve assay. RT-qPCR, haemolysis assay, lactate dehydrogenase release assay and chemotaxis assay were used to evaluate the effects of the PLNAs on inhibiting agr QS. A mouse skin infection model was employed to test the protective effect of the PLNAs in vivo. None of the PLNAs were found to be bacteriostatic or bactericidal in vitro. However, one PLNA, PLNA34, showed strong ability to suppress expression of agrA and the effector molecule RNAIII in USA300 LAC strain. Furthermore, PLNA34 inhibited the expression of virulence genes that are upregulated by agr, including hla, psmα, psmβ and pvl. The haemolytic activity of the supernatants from PLNA34-treated bacteria was also dramatically reduced, as well as the capacity to lyse and recruit neutrophils. Moreover, PLNA34 showed high levels of protection in the CA-MRSA mouse skin infection model.

CONCLUSIONS

The anti-agrA PLNA34 can effectively inhibit the agr QS and suppress CA-MRSA pathogenicity.

SIGNIFICANCE AND IMPACT OF THE STUDY

agrA is a promising target for the development of antisense oligonucleotides to block agr QS.

Association analysis of imbalanced interhemispheric functional coordination and early therapeutic efficacy in major depressive disorder: Evidence from resting state fMRI

Introduction

Emerging evidences indicate that the alteration of interhemispheric functional coordination may be involved in the pathogenesis of major depressive disorder (MDD). In present study, we aim to explore the potential marker by using the voxel-mirrored homotopic connectivity (VMHC) approach, which may be contributing to predict the clinical prognosis in MDD.

Methods

Eighty-two MDD patients and 50 normal control (NC) subjects participated in this study. We divided the MDD group into unremitted and remitted group according to the reduction rate of Hamilton Rating Scale for Depression (HAMD) within 2 weeks.

Results

The study detected significantly decreased VMHC in bilateral precuneus (pCu), inferior temporal gyrus (ITG) and increased VMHC in middle frontal gyrus (MFG) and caudate nucleus when compared remitted depression (RD) group to unremitted depression (URD) group. Meanwhile, when compared with NC group, the URD group presented reduced VMHC in bilateral cerebellum anterior lobe, thalamus and postcentral gyrus. Furthermore, the VHMC in media frontal gyrus, postcentral gyrus and precentral gyrus were significantly decreased in RD group. Correlation analysis suggested that reduced VMHC in bilateral pCu was negatively correlated with the baseline HAMD score of URD (r = −0.325, P = 0.041). Receiver operating characteristic (ROC) curve indicated that three regional VMHC changes could identify depressed patient with poorer treatment response: ITG [area under curve (AUC) = 0.699, P = 0.002, 95% CI = 0.586–0.812], MFG (AUC = 0.692, P = 0.003, 95% CI = 0.580–0.805), pCu (AUC = 0.714, P = 0.001, 95% CI = 0.603–0.825).

Conclusion

The current study combined with previous evidence indicates that the subdued intrinsic interhemispheric functional connectivity might represents a novel neural trait involved in the pathophysiology of MDD.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Decreased interhemispheric functional coordination underlying the cognitive impairment in late-onset depression

Background

The intuitive association between cognitive dysfunction in late onset depression (LOD) and the aberrant functional activity in the brain's default-mode network (DMN) has prompted interest in exploring the role of the DMN in LOD. The altered pattern of resting state voxel-mirrored homotopic connectivity (VMHC) in cognitive processes is not yet well understood in LOD.

Methods

The study was designed to examine the implicit coupling between the alteration of interhemispheric functional coordination and cognitive impairment in LOD. Thirty-one LOD patients and 37 matched healthy controls (HC) underwent neuropsychological tests and functional magnetic resonance imaging (fMRI) in this study.

Results

Compared to HC group, attenuated VMHC in superior frontal gyrus, superior temporal gyrus, posterior cerebellar lobe, postcentral and precentral gyrus was observed in LOD. Neuro-behavioral relevancy approach revealed that the imbalanced interhemispheric functional coordination in bilateral cerebellum was positively correlated with the performance of trail making test in LOD (r = 0.367, P = 0.040).

Conclusion

Altered linkage pattern of intrinsic homotopic connectivity and cognition was firstly investigated in LOD, and it would provide a novel clue to reveal the neural substrates underlying the cognitive dysfunction in LOD.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Impact of cataract surgery on vision-related life performances: the usefulness of Real-Life Vision Test for cataract surgery outcomes evaluation

PURPOSE

Real-Life Vision Test (RLVT) is a newly developed performance-based measures of functional vision. This present study is designed to determine whether it could be a meaningful assessment for cataract surgery outcomes evaluation.

PATIENTS AND METHODS

Age-related cataract patients (56) who scheduled for bilateral cataract surgery and 44 age-matched controls were evaluated by four types of measurements: (1) demographic, medical, cognitive and depressive evaluation, and the reaction time testing; (2) clinical measures (visual acuity, contrast sensitivity, stereopsis, and color perception); (3) the 25-item National Eye Institute's Visual Functioning Questionnaire (NEI-VFQ); (4) the RLVT. Spearman's coefficients and multiple regression analysis were conducted to investigate the relationship among RLVT, clinical measures, and self-report assessment of visual function.

RESULTS

The results of RLVT, clinical measures, and NEI-VFQ total scores were improved significantly after cataract surgery. There were no differences between control subjects and post-surgery patients with respect to NEI-VFQ-25 total scores, self-rating depression scale scores and three tasks of RLVT. Change of RLVT was significantly associated with the change of clinical measures in the cataract group. Multiple regression analysis demonstrated that change of distance, intermediate, and near visual acuity, and binocular contrast sensitivity were significant predictors of improvements of RLVT.

CONCLUSIONS

Cataract surgery could improve real-world visual ability effectively for cataract patients. Our study highlights the potential usefulness of RLVT as an adjunct to the current outcomes evaluation system for cataract surgery. The use of RLVT combined with clinical and self-survey methods may be the comprehensive strategy to manifest the impact of cataract surgery on patients' overall vision-related quality of life.

Annexin A5 promotes macrophage activation and contributes to pulmonary fibrosis induced by silica particles

OBJECTIVE

To investigate the contributions and underlying molecular mechanisms of annexin A5 toward silica-induced pulmonary fibrosis.

METHODS

Male C57BL/6 mice were randomly divided into three groups and instilled intratracheally with silica, saline, or air. Mice were euthanized at 3, 7, 14, or 28 days following treatment. Annexin A5 levels in serum and lung tissues were detected by enzyme-linked immunosorbant assay (ELISA) assays or Western blots. The association of annexin A5 levels with silica-induced lung fibrosis was further investigated in the macrophage cell line, RAW264.7. Following exposure of these cells to silica at a concentration of 200 μg/ml for 6 or 12 h, the expression levels of transforming growth factor β1 (TGF-β1), interleukin 1α (IL-1α), Fas ligand (FasL), and their downstream targets were evaluated by Western blots. Furthermore, annexin A5 and FasL were knocked down by small interfering ribonucleic acid (siRNA) and TGF-β1 secretion into the cell culture medium was measured by ELISA assays or Western blots.

RESULTS

Mice treated with silica demonstrated lung fibrosis at 28 days following exposure, whereas, in controls, only mild and transient inflammation was evident at day 3 and day 7 postinstillation and was not present at day 14. Furthermore, silica-exposed mice exhibited significantly (p < 0.05) elevated levels of annexin A5 in serum and lung tissues, relative to control groups. Consistent with these findings, silica exposure of RAW264.7 cells for 6 or 12 h, led to an annexin A5-dependent increase in the expression levels of TGF-β1, IL-1α, FasL, and their downstream target molecules. These silica-induced changes were reversed by siRNA-mediated knockdown of annexin A5, but downregulation of FasL led to increased annexin A5 expression and reduced levels of TGF-β1, IL-1α, and FasL downstream target molecules.

CONCLUSIONS

These findings define a role of annexin A5 in promoting macrophage activation via Fas/FasL pathways in silica-induced lung fibrosis.

Multicomponent gas analysis using broadband quantum cascade laser spectroscopy

We present a broadband quantum cascade laser-based spectroscopic system covering the region between 850 and 1250 cm(-1). Its robust multipass cavity ensures a constant interaction length over the entire spectral region. The device enables the detection and identification of numerous molecules present in a complex gas mixture without any pre-treatment in two minutes. We demonstrate that we can detect sub-ppmv concentration of acetone in presence of 2% of water at the same wavenumber region.

Comparisons of egg quality traits, egg weight loss and hatchability between striped and normal duck eggs

1. The egg quality of striped and normal duck eggs was compared to determine why striped eggs show decreased hatchability. A total of 430 eggs, obtained from a Pekin duck breeder flock aged 50-65 wks, were used in three experiments. The eggs were weighed and assigned randomly to measure egg quality traits, egg weight (EW) loss and hatchability during incubation. 2. There were no significant differences between egg types in terms of egg shape index, eggshell strength and thickness, albumen height, Haugh unit, yolk colour, weight of the eggshell with or without membranes, calcium, phosphorus, copper and manganese contents in the eggshell (with the inner and outer membranes or without the inner membrane), albumen weight, dry matter of albumen, crude protein (CP) of thick albumen and pH of the thick albumen. 3. The weight of eggshells with membranes, weight of thick albumen and CP of thin albumen in striped eggs were lower than those in normal eggs. 4. The thin albumen in striped eggs was heavier than that in normal eggs. The pH of the thin albumin in striped egg was significantly higher than that in normal eggs. 5. There were no significant differences in EW loss during incubation or duckling weight between striped and normal eggs. However, the hatchability of striped eggs was lower. 6. The lower weight of the eggshell inner membrane and thick albumen, lower CP content and higher pH in the thin albumen of striped eggs might contribute to lower hatchability.

Development of the fetal cerebral cortex in the second trimester: assessment with 7T postmortem MR imaging

BACKGROUND AND PURPOSE

Few investigators have analyzed the fetal cerebral cortex with MR imaging of high magnetic strength. Our purpose was to document the sulcal development and obtain quantitative measurements of the fetal brain in the second trimester.

MATERIALS AND METHODS

The brains of 69 fetal specimens, with GA 12-22 weeks, were first scanned on a 7T MR imaging scanner. Then the sequential development of the different fissures and sulci was analyzed, and quantitative measurements of the cerebral cortex were obtained.

RESULTS

A new chronology of sulcal development during 12-22 weeks GA was summarized. Before 12 weeks, few sulci were present; by 16 weeks, many sulci were present. The 16th week could be considered the most intensive time point for sulcal emergence. Most sulci, except for the postcentral sulcus and intraparietal sulcus, were present by 22 weeks GA. Measurements of the fetal brains, each with different growth rates, linearly increased with GA, but no sexual dimorphisms or cerebral asymmetries were detected.

CONCLUSIONS

The second trimester is the most important phase, during which most sulci are present and can be clearly shown on 7T postmortem MR imaging. It is apparent that the specific time during which neuropathologic features of sulci appear, previously thought to be well understood, should be redefined. Quantitative data provide assistance in the precise understanding of the immature brain. The present results are valuable in anatomic education, research, and assessment of normal brain development in the uterus.

Gene expression profiling of Escherichia coli in response to interactions with the lettuce rhizosphere

AIMS

The objective of this study was to examine transcriptional changes in Escherichia coli when the bacterium was growing in the lettuce rhizoshpere.

METHODS AND RESULTS

A combination of microarray analyses, colonization assays and confocal microscopy was used to gain a more complete understanding of bacterial genes involved in the colonization and growth of E. coli K12 in the lettuce root rhizosphere using a novel hydroponic assay system. After 3 days of interaction with lettuce roots, E. coli genes involved in protein synthesis, stress responses and attachment were up-regulated. Mutants in curli production (crl, csgA) and flagella synthesis (fliN) had a reduced capacity to attach to roots as determined by bacterial counts and by confocal laser scanning microscopy.

CONCLUSIONS

This study indicates that E. coli K12 has the capability to colonize lettuce roots by using attachment genes and can readily adapt to the rhizosphere of lettuce plants.

SIGNIFICANCE AND IMPACT OF THE STUDY

Results of this study show curli production and biofilm modulation genes are important for rhizosphere colonization and may provide useful targets to disrupt this process. Further studies using pathogenic strains will provide additional information about lettuce-E. coli interactions.